In uk.d-i-y, Aenuff wrote:

Basically I need about 10 of these to wire up storage radiators. No they're
not on economy seven, are just on a normal ring. At the moment they simply
plug into a socket with a timer on the plug! It works but people keep
unplugging / bypassing the timers etc. Considering these are all new heaters
I'd like to have them hard wired to a spur.

Gag. 10 storage heaters, on 'a' ring? You jest, surely: even for the
lowest-rating storage heaters of 1kW you'd have 10kW = 40A loading on that
poor little ring; with 2kW jobbies you'd have 80A! And if your tenants,
students, migrant workers or whatever keep bypassing the timer, maybe
they're cold, meaning the heaters are underpowered for the job they're
trying to do? Are all these heaters in one property with one main supply,
or are they spread among several houses?

Fixed heaters in regular use like these ought to have their own dedicated
radial circuits (1-2 heaters per circuit depending on their rating). Then
you can run dedicated switching for them back at/near the consumer unit (hmm,
sounds just like an Economy7 setup, doesn't it?). Immersion-heater timers
switch up to 3kW, and in some out-of-the-way padlocked cupboard might be
good enough for your needs; beyond that lies the realm of control systems
and contactors. But can you really not fork out for pukka dedicated-circuit
Economy7 in the property/ies? Then you get your time-switching done for
you, with no occupier intervention, and a far cheaper rate for the
nighttime electricity thrown in... Or even a gas-powered wet CH system,
if the property/ies have a mains gas supply!?

Stefek